Watercraft especially useful for the recovery of oil

ABSTRACT

A watercraft is disclosed which comprises a body member of the catamaran-type having spaced-apart twin hulls between which is disposed an oil recovery system which can recover oil (for instance in the form of an oil slick) which has been properly directed by the hulls of the craft. The watercraft has a generally centrally located turning axis; first and second propulsor means secured to the body member for accepting water at an inlet opening thereof and discharging water at a higher velocity at discharge openings thereof; first thrust generating means in fluid communication with the discharge opening of the second propulsor means for generating thrust in a first direction about the turning axis; second thrust generating means in fluid communication with the discharge opening of the first propulsor means for generating thrust in the first direction about the turning axis; third thrust generating means in fluid communication with the discharge opening of the first propulsor means for generating thrust in a second direction about the turning axis; fourth thrust generating means in fluid communication with the discharge opening of the second propulsor means for generating thrust in the said second direction about the turning axis; and maneuverability control means on the body member for selectively establishing an nonestablishing the fluid communication between the first and second propulsor means and the first, second, third, and fourth thrust generating means respectively. Additionally each of the propulsor means may be removably secured to the rear of the body member and includes a particularly advantageous construction comprising a multifunction one-piece casting; a propulsor housing secured to the undersurface of a rearwardly extending portion of the one-piece casting; a prime mover secured to the upper surface of the said rearwardly extending portion of the one-piece casting; and a water gathering collection chamber secured to the propulsor housing for helping to establish the necessary pressure head used in the maneuverability system of the craft.

United States Patent Budris et al.

[ 1 Mar. 7, 1972 [54] WATERCRAFT ESPECIALLY USEFUL FOR THE RECOVERY OF OIL [72] Inventors: Allen R. Budris, Nutley; Frank J. Mc-

Gowan, Murray Hill; Lewis M. Evans, Upper Montclair; Theodore J. Wayne, Linden, all of N.J.; Eric E. Lithen, Garden City, Long Island; Charles B. Darcy, Glen Head, Long Island, both of N.Y.

131 Assignee: Worthington Corporation, Harrison, NJ.

221 Filed: Feb. 2, 1970 211 Appl. No.: 7,650

Primary Examiner-Trygve M. Blix Attomey-Lemer, David & Littenberg ABSTRACT A watercraft is disclosed which comprises a body member of the catamaran-type having spaced-apart twin hulls between which is disposed an oil recovery system which can recover oil (for instance in the form of an oil slick) which has been properly directed by the bulls of the craft. The watercraft has a generally centrally located turning axis; first and second propulsor means secured to the body member for accepting water at an inlet opening thereof and discharging water at a higher velocity at discharge openings thereof; first thrust generating means in fluid communication with the discharge opening of the second propulsor means for generating thrust in a first direction about the turning axis; second thrust generating means in fluid communication with the discharge opening of the first propulsor means for generating thrust in the first direction about the turning axis; third thrust generating means in fluid communication with the discharge opening of the first propulsor means for generating thrust in a second direction about the turning axis; fourth thrust generating means in fluid communication with the discharge opening of the second propulsor means for generating thrust in the said second direction about the turning axis; and maneuverability control means on the body member for selectively establishing an nonestablishing the fluid communication between the first and second propulsor means and the first, second, third, and fourth thrust generating means respectively. Additionally each of the propulsor means may be removably secured to the rear of the body member and includes a particularly advantageous construction comprising a multifunction one-piece casting; a propulsor housing secured to the undersurface of a rearwardly extending portion of the one-piece casting; a prime mover secured to the upper surface of the said rearwardly extending portion of the one-piece casting; and a water gathering collection chamber secured to the propulsor housing for helping to establish the necessary pressure head used in the maneuverability system of the craft.

64 Claims, 8 Drawing Figures PMENTEBMAR 7 m2 SHEET 1 BF 7 v 98 W m9 8N lwmw mm mm on wmm INVENTORS.

ES 8. DA

DAVID a LITTENBERG' LERNER,

ATTORNEYS PATENTED 7 I973 SHEET 5 OF 7 PATENTEDHAR 7 1972 SHEET 8 BF 7 FIG. 7

PAIENTEDMAR 71972 3,646,901

sum 7 OF 7 OE ul mMJFPOKIh wmmhmDmIk mnzm FIOE WATERCRAFT ESPECIALLY USEFUL FOR THE RECOVERY OF OIL BACKGROUND OF THE INVENTION This invention relates to watercraft or boats; more particularly to a highly maneuverable watercraft of the jet propulsion type which is particularly adapted to function as a portion of any overall oil recovery system, and even more particularly to an improved maneuverability system for boats of this type and to improved propulsor systems therefor.

As recent publicity has emphasized, water pollution from oil slicks and the like is an extremely dangerous problem which has continually plagued engineers, sanitation personnel, etc..

Techniques frequently employed to rid lakes, ports, rivers and other bodies of water of oil slicks usually involve either chemical treatment of the oil slick, which has been found to be unpractical, expensive and inefficient, or physical removal of the slick by direct suction pumps which inefficiently results in significantly more water being removed than oil.

Recently, oil recovery systems have been developed which employ a roller covered with a liquid absorbing material which is partially submerged and continually rotated in the oil slick. A cooperating pressure roller is placed in juxtaposition to the roller and continually squeezes the oil from the roller cover (into appropriate receptacles) as the oil-filled cover rotates up out of the water. Unfortunately, until the present invention, little has been done to effectively employ such systems as part of an overall watercraft based oil recovery system. Additionally, and as a necessary consequence, until the present invention little work has been done in developing an appropriate watercraft therefor, and even less has been accomplished in developing a jet-propelled watercraft which can efficiently function under the heavy duty, low speed requirements inherent in such a system.

For example, in common high speed jet-propelled watercraft, maneuverability, e.g., steering, can be accomplished with convention rudder and/or steerable nozzles techniques. However, the necessary maneuverability desired at low speeds presents different problems. Similarly, little work has been done to develop jet propulsors which are designed for and have particular applicability to low speed watercraft. For exaxis; and maneuverability control means on the body member for selectively establishing and nonestablishing the fluid communication between the first and second propulsor means and the first, second, third and fourth thrust generating means respectively. The above-defined arrangement establishes an extremely maneuverable watercraft, especially maneuverable at low speeds, wherein either propulsor means in and of itself, is capable of generating clockwise and counterclockwise Y thrust about the turning axis of the craft.

ample, such problems of easy assembly and disassembly, simple replacement of entire propulsor units and parts thereof, minimizing the total number of parts, etc., are not major considerations for designers of high speed pleasure boats, whereas in the area of heavy-duty work boats, such problems as these are of paramount importance if the craft is to have long useful life.

SUMMARY OF THE INVENTION With the above-noted problems in mind, the instant invention broadly provides a watercraft of the catamaran type having a pair of redundant hulls between which is operatively disposed an oil slick recovery system. By virtue of various other inventive concepts disclosed herein, the craft itself is especially useful for low speed heavy duty application and includes a body member having a generally centrally located turning axis; first and second propulsor means secured to the body member for accepting water at an inlet opening thereof and discharging water at higher velocity at discharge openings thereof; first thrust generating means in fluid communication with the discharge opening of the second propulsor means for generating thrust in a first direction about the turning axis; second thrust generating means in fluid communication with the discharge opening of the first propulsor means for generating thrust in the first direction about the turning axis; third thrust generating means in fluid communication with the discharge opening of the first propulsor means for generating thrust in a second direction about the turning axis; and fourth thrust generating means in fluid communication with the discharge opening of the said second propulsor means for generating thrust in the second direction about the turning As a particularly advantageous feature of the present invention, each of the propulsor means is provided with a collection chamber adjacent the discharge opening thereof which collection chamber functions to collect water discharged by the respective propulsor means and thereby produce relatively higher pressure heads useful for supplying the various thrusters of the above-defined maneuverability system without introducing friction and turbulent losses into the main jetstream which would otherwise reduce the top speed of the boat. The collection chambers each include a gate movable between a first position in which an exit opening of the collection chamber is completely open; a second position in which the exit opening of the collection chamber is closed; and any position intermediate of these two extremes. in this manner, the movable gate can be utilized to preselectively vary the pressure head established in the respective collection chambers. Preferably, the exit openings of the collection chambers are in a rearward direction with respect to the craft, and accordingly, with the respective gates in any of their various open positions, the water issuing from the collection chambers can be directly utilized to generate forward thrust to propel the craft in its forward direction. It should be pointed out that with the respective gates in the full open position the water jets detach at the propulsor discharge openings and bypass the walls of the collection chambers, thus eliminating collector wall losses.

As a further feature of the maneuverability control system of the instant invention, forwardly directed thrusters are provided in fluid communication with the respective collection chambers. Thus with the respective gates of the collection chamber occupying either the closed or any one of their partially closed positions, a certain amount of water issuing from the propulsor means will be diverted through the forwardly directed thruster to generate a rearward thrust which will propel the craft in a rearward direction.

As a further particular advantageous feature of the instant invention, the various side and rear thrusters which establish the maneuverability system can be individually controlled (opened and closed) by means of pivoting vanes positioned in fluid conduits joining the output of the propulsor means with the thrusting jets themselves. Such pivoting vanes are selec tively controlled by manually operable control sticks located on a control console. As will be explained in greater detail, the particular layout of control sticks on the control panel is preselectively chosen and laid out to facilitate operation even by relatively unskilled personnel.

As a further feature of the instant invention, there is provided propulsor units which are particularly applicable in a heavy-duty, low speed watercraft environment and particularly adapted for use in the oil recovery system hereof and in conjunction with the above-described maneuverability system. Specifically, each of the propulsor units of the instant invention is of modular construction and particularly adapted to be removed from and secured to preexisting craft. Additionally, each of the propulsor units comprises a one-piece detachable member, preferably a casting, which includes a rearwardly extending multifunction upper portion to the undersurface of which can be easily secured the impeller containing propulsor housing of the propulsor means, and to the upper surface of which can be easily and conveniently secured the prime mover associated with the impeller. The rearwardly extending upper portion of the detachable member additionally includes a passageway through which the impeller drive shaft and the output shaft of the prime mover may be conveniently joined for example by means of a clutch assembly. In addition, the detachable member includes: a hollow forward portion which houses flotation material; a flow channel by which water is directed to the impeller located in the propulsor housing; a forwardly located inturned flange surface by which the entire propulsor housing can be conveniently and easily secured to the rear of the hull portion of the craft; and supports a strut-screen assembly for preventing debris from entering the flow channel.

Accordingly, it is an object of the instant invention to provide a watercraft of the catamaran type having a pair of twin hulls between which is operatively disposed an oil slick recovery system.

Another object of the instant invention is to provide a low speed jet-propelled watercraft having a highly effective, fail safe maneuverability system which can provide clockwise and counterclockwise rotation, even if one of the two propulsor means of the craft is disabled.

Another object of the instant invention is to provide such a watercraft which includes a plurality of sidewardly directed thrust generating means which are selectively supplied from the discharge end of a pair of associated jet propulsor means.

Still another object of the instant invention is to provide such a watercraft wherein the jet propulsor means are each provided with collection chambers which may be selectively closed to help establish necessary pressure heads useful in supplying fluid to the aforementioned thrusters.

Another object of the instant invention is to provide such a watercraft which includes forwardly directed rear thrusters in selective fluid communication with the aforementioned collection chambers for generating rearwardly directed thrust.

Still another object of the instant invention is to provide such a watercraft and steering maneuverability propulsion system therefor which includes a manually operable control system preferably and preselectively arranged to facilitate operation even by unskilled personnel.

Another object of the instant invention is to provide propulsor means especially adapted for use on low speed heavy-duty work craft.

Yet another object of the instant invention is to provide such propulsor means which are easily secured to and removable from the rear of preexisting craft.

Another object of the instant invention is to provide such a propulsor means which includes a detachable member, preferably a casting, which includes a forward surface defined by an inturned flange portion; a hollow cavity; a flow channel; and a rearwardly directed upper portion having a passageway therethrough.

Yet another object of the instant invention is to provide such a detachable member for a propulsor means wherein the upper surface of the rearwardly extending portion thereof is utilized for the convenient and easy mounting of prime mover, and the lower surface of the aforementioned rearwardly extending upper portion of the detachable member is utilized for the securement of a propulsor housing in which is located the driving impeller of the propulsor means.

Yet another object of the instant invention is to provide a fluidtight seal for passing the impeller drive shaft through the aforementioned propulsor housing whereby it may be joined, for example by a clutch arrangement, to the output shaft of the aforementioned prime mover.

Other objects in a fuller understanding of the instant invention may be had by referring to the following specification and drawings in which:

FIG. 1 is a side view of the watercraft of the instant invention;

FIG. 2 is a plan view of the instant invention;

FIG. 3 is an enlarged side view, partly in section, of portions of the instant invention;

FIG. 4 is an enlarged sectional view, of a portion of the propulsor housing and impeller employed in the propulsor means of the instant invention;

FIG. 5 is an enlarged plan view of the detachable member utilized in the propulsor means of the instant invention;

FIG. 6 is a view taken along lines 66 of FIG. 5;

FIG. 7 is a partial perspective view, partly in section, of the kickup rudder assembly of the instant invention; and

FIG. 8 is a partially schematic plan view of the control console utilized in the instant invention.

Turning to the Figures, wherein like numerals are used to designate like parts, there is illustrated the watercraft based oil recovery system 10 of the instant invention. Broadly speaking, the system 10 includes a catamaran-type vessel 12 including a pair of buoyant hulls 14 and 1.6 to the rear of each of which is secured, in a manner to be further described, propulsor means broadly designated 18 and 20 respectively. As will be further explained, the propulsion and maneuverability system of the system 10 is operated from a control console 22 located under a protective pilot housing 23.

For the vessel to function as part of an oil recovery system, the deck 13 thereof is provided with an enlarged opening 15 in and about which is located an oil recovery system broadly designated 24. Although the recovery system 24 per se forms no part of the instant invention, for the purpose of understanding the manner in which it functions in the instant invention, it might be noted that broadly the system 24 includes a roller 25 covered with an absorbent outer covering 27. The roller 25 is lowered through the opening 15 into the water and rotated by a driving mechanism including a prime mover 29, appropriate clutch and reducing gear mechanism broadly designated 31, and conventional pulleys (not shown). As the roller is rotated, the absorbent covering 27 comes up out of the water and is engaged by a cooperating presser roller 33 which thereby squeezes the oil from the roller covering into appropriate onboard storage devices (not shown).

It will be appreciated that the twin hull arrangement of the catamaran-type vessel 12 effectively channels the oil slick towards the roller 25 thereby greatly increasing the efficiency of the overall system. Additionally, a pair of bow wings 26 may be secured to the bow ends of the twin hulls l4 and 16 to provide an enlarged entrance throat 28.

It will be understood that although the invention is hereby described in connection with an oil recovery system, it may have a variety of alternative or multiple function uses such as: trash gathering, weed cutting, fire fighting, oil boom laying, divers work boat, personnel and material carrier, office of platform workboat, commercial fishing boat, private pleasure boat, etc.

Turning now to the maneuverability and propulsion system, and as will be described in greater detail, each of the propulsor means 18 and 20 functions to accept water at an inlet opening thereof (designated 30 in FIG. 1) and to discharge the water at a higher velocity at a discharge opening designated 32 in FIG. 1. In the preferred embodiment of the invention, collection chambers designated 34 and 36 in the Figures, are secured in fluid communication to the discharge openings 32 of the respective propulsor means 18 and 20 and are employed for containing and collecting the discharged water for the purpose of generating higher pressure heads useful for the various thrusters discussed below.

With reference to H6. 2, an imaginary turning axis 38, preferably at the center of bouyancy is established by the intersection of an imaginary longitudinal axis 40 and an imaginary horizontal axis 42. For ease of identification, these two axes define quadrant I, quadrant II, quadrant III and quadrant IV, disposed consecutively about the turning axis 38 in a clockwise direction beginning in the upper left-hand corner of FIG. 2. Disposed in quadrant IV of the vessel 12 is a first thrust generating means designated No. l thruster 44; disposed in quadrant II is a second thrust generating means designated No. 2 thruster d6; disposed in quadrant l is a third thrust generating means designated No. 3 thruster 48; and disposed in quadrant III is a fourth thrust generating means designated No. 4 thruster 50. Each of the various thrust generating means 44,, 46, 48 and 50 may comprise simply the open end of a conduit or as suggested in FIG. 2, may comprise a reduced diameter end of an open conduit.

By means of a conduit 52, the first thrust generating means 44 is in fluid communication with the collection chamber 34 and hence the discharge opening 32 of the propulsor means 18 (designated in FIG. 2 as the No. 2 propulsor 18). Similarly, by means of a fluid conduit 54, the second thrust generating means 46 is in fluid communication with the collection chamber 36 and hence the discharge opening 32 of the No. l propulsor means 20. In like manner, by means of a fluid carrying conduit 56, the third thrust generating means 48 is in fluid communication with the collection chamber 36, and hence the discharge opening 32 of the second propulsor means 20 (designated the No. 1 propulsor means 20). Finally, by means of a fluid conduit 58, the fourth thrust generating means 50 is in fluid communication with the collection chamber 34 and hence the discharge opening 32 of the number two propulsor means 18.

From the above, it will be appreciated that with the first propulsor means 20 operating to discharge water at high pressure from its discharge opening 32 thereof into the collection chamber 36, it is possible by virtue of the conduits 56 and 54 to issue water out of the third thrust generating means 48 and the second thrust generating means 46. In fact, by control means to be discussed in greater detail, it is possible for the operator to issue water out of either the third thrust generating means 48, the second thrust generating means 46, or both thrust generating means 48 and 46.

Similarly, with the second propulsor means 18 functioning to discharge water from its discharge opening 32 into the collection chamber 34, it is possible, by virtue of the conduits 52 and 58, to issue water out of the first thrust generating means 44 and the fourth thrust generating means 50. By control means to be described, the operator of the craft has the choice of issuing water from the first thrust generating means 44 alone, the fourth thrust generating means 50 alone, or both.

From the description presented thus far, the excellent maneuverability of the watercraft 12 should now become apparent. Specifically should the operator desire to move the craft sideways in a port direction (downwardly in FIG. 2), he merely causes the number three thruster 48, and the number two thruster 46 to issue water thereby generating thrust depicted by the arrowheads 60 and 62 to move the craft in the port direction. Similarly should the operator desire to move the craft 10 in the starboard direction (upward in FIG. 2), he merely causes the number one thruster 44 and the number four thruster 50 to issue water which thereby generates thrust depicted by the arrowheads 64 and 66 to move the craft in the starboard direction.

Should the operator desire to rotate the craft clockwise about the turning axis 38 thereof, he causes the first thrust generating means 44 and the second thrust generating means 46 to issue water thereby creating clockwise turning moments due to the forces depicted by the arrows 64 and 62 respectively. Should the operator desire to rotate the craft counterclockwise about the turning axis 38, he causes the number three thrust generating means 48 and the number four thrust generating means 50 to issue water thereby creating counterclockwise turning moments due to the forces designated by the arrows 60 and 66 respectively.

As a particularly advantageous feature, let it be assumed that the number two propulsor means 18 is completely disabled for some reason, and only the number one propulsor means 20 is still functioning. Should the operator desire to effect clockwise rotation about the turning axis 38, he causes number two thrust generating means 46 to operate. Should he desire to effect counterclockwise rotation about the turning axis 38, he causes the number three thrust generating means 48 to operate. It will be appreciated that because of the thrust generating arrangement of the instant invention, both clockwise and counterclockwise motion can be effectuated with only one propulsor means in operation.

Turning to FIG. 3, there is shown an enlarged, partly sectioned view of the first propulsor means 20 and the manner in which it cooperates with the collection chamber 36, the fluid carrying conduits, and the thrusters associated therewith. The number two propulsor means 18 is identical, the only exception being the directional orientation of the associated conduits and thrusters.

Specifically, the propulsor means 20 includes a member 70, preferably a one-piece aluminum casting, which is removably secured to the rear of the hull 16. A prime mover 72 is secured on the upper surface 74 of a rearwardly extending upper portion 76 of the detachable member 70. Secured to the undersurface 78 of the rearwardly extending upper portion 76 is a propulsor housing 80 within which is located an impeller 82 shown in FIG. 4. The propulsor housing 80 terminates in an outlet opening which defines the aforementioned discharge opening 32 of the propulsor means 20. Secured about the.

discharge opening 32 by appropriate circumferentially located fastening bolts 82 is the generally cylindrical collection chamber 36, the rearward end of which terminates in an exit opening 84.

Pivotally mounted about pivot points 86 provided on opposite sides of the collection chamber 36 is an arcuate gate 88 (strengthened by stiffening members 90) which is movable between an open position (illustrated in FIG. 3) in which the exit opening 84 of the collection chamber is completely open, and a second, closed position (wherein the lower end 92 of the gate 88 abuts a fixed stop 94) in which the exit opening 84 of the chamber 36 is completely closed. It will be appreciated that when the gate 88 occupies its completely closed position (and as the gate approaches the closed position), it will collect the water issuing from the discharge opening 32 of the propulsor means 20 to thereby generate a pressure head which can be used for the various thrusters described above. It will also be appreciated that as the gate 88 is moved towards its open position water issuing from the discharge opening 32 of the propulsor means 20 may exit the collection chamber in a rearward direction through the opening 84 thereof to provide a forwardly directed thrust which will propel the craft 10 in a forward direction.

Also illustrated in FIG. 3 is the fluid conduit 56 connected at one end thereof by a flanged collar 96 to the collection chamber 36. Similarly, fluid conduit 54 is shown angled outwardly with respect to the plane of the paper upon which FIG. 3 is drawn. As noted previously, conduit 54 terminates in the number two thrust generating means 46 which in FIG. 3 is merely the open end of the conduit 54.

Also shown in FIG. 3 is a downwardly directed, forwardly extending conduit 100 which terminates in a forwardly directed fifth thrust generating means 102 which may constitute the open end of the conduit 100. Although not clearly seen in FIG. 3, the opposite end of the fluid conduit 100 is secured in fluid communication to the collection chamber 36. It will be appreciated that with the gate 88 in its closed position, and conduit 100 in an open nonblocked condition, fluid under pressure can be issued from the fifth thrust generating means 102 in a forward direction to thereby provide a rearwardly directed thrust for propelling the craft 10 in a rearward direction. A similar arrangement for rearwardly directed thrust is provided in conjunction with the second propulsor means 18, with the forwardly directed sixth thrust generating means 104 and the associated fluid conduit 106 thereof being the only elements visible in FIG. 1.

To selectively control the issuance of water from the various thrusters described above, there is provided in each of the respective conduits a pivoting vane which is movable between a first position which blocks the respective conduit in which it is located and a second position which opens the respective conduit to establish fluid communication between the discharge opening of the respective propulsor means (by way of the respective collection chamber) and the associated thrust generating means. For example, as illustrated in FIG. 3, a generally circular vane 108 is rotatably mounted about an axis 110 positioned in the fluid conduit 56 which joins the collection chamber 36 and the number three thrust generating means 48. Positioned on the outside of the conduit 56 and rotatable about the axis 110 with the vane 108 is a bellcrank level 112 which can be rotated in clockwise and counterclockwise directions with respect to the axis 110 by a conventional, sheathed push, pull cable 114 directly connected to appropriate control sticks on the aforementioned control panel 22 in a manner which will be further described. It will be appreciated that by appropriate movement of the cable 114, the lever 112 and hence the vane 108 can be easily moved between the blocking position illustrated at 108 and the open position illustrated at 108'.

A similar arrangement is provided in the conduit 54 and 100 to selectively control the operation of the number two thrust generating means 46 and the reverse thrust generating means 102. For example, in FIG. 3, the pivoting vane 118 and bellcrank lever 120 associated with conduit 54 are visible as well as the pivoting vane 122 and lever 124 associated with the conduit 100.

It will also be appreciated that similar pivoting vane arrangements are present in the conduits 52, 58 and 106 (not visible in FIG. 3) to control the thrust generating means 60, 50 and 104 respectively. Similarly, control cables are provided to permit the various control sticks of FIG. 8 to control the associated pivoting vanes.

Finally, cable schematically illustrated at 126 in FIG. 3 is provided to allow the operator to move the gate 88 between its open and closed position by means of a control stick 130 on the control panel 22 of FIG. 8. A second control stick 132 and actuating cables (not shown) are provided to control the movement of the gate 89 associated with the collection chamber 34 of the number two propulsor means 18.

Turning to FIG. 8, the various operating control sticks of the control panel 22 will now be described. The control stick 134 is connected by appropriate push pull cable (and the necessary bellcranks, etc.,) to control'the pivoting vane 108 positioned in the conduit 56 and thereby effect the operation of the number three thrust generating means 48. When the control stick 134 occupies the solid line position illustrated in FIG. 8, the associated pivoting vane 108 is in its blocking position with respect to the conduit 56 and the number three thrust generating means 48 is inoperative. Should the operator slide the control stick 134 in the channel 136 to the phantom position 134, the associated vane 108 will pivot to its phantom position 108 and allow the number thrust generating means 48 to generate thrust in the direction of arrow 60 of FIG. 2.

Similarly, the control stick 138 controls the movement of the pivoting vane 118 located in the conduit 54 of FIG. 2 and 3 and thereby controls the operation of the number two thrust generating means 46. With the control stick 138 in the solid line position of FIG. 8, the pivoting vane 118 associated therewith in its blocking position and the number two thrust generating means 46 is inoperative. When the operator slides the control stick 138 in the channel 140 to the phantom position 138, the associated vane 118 will pivot to its open position allowing fluid to be issued out of the number two thrust generating means 46 to generate thrust in a direction of arrow 62 of FIG. 2.

In like manner, the control stick 142 controls the movement of pivoting vane in the conduit 52. When the control stick 142 is in the solid line position of FIG. 8, the pivoting vane is in its blocking position and the number one thrust generating means 44 is inoperative. When the operator moves the control stick 142 in the channel 144 to the dotted position illustrated at 142, the pivoting vane moves to its open position to allow water to issue out of the number one thrust generating means 44 to generate thrust in the direction of arrowhead 64 of FIG. 2. Similarly, the control stick 146 controls the pivoting vane in the fluid conduit 58 of FIG. 2. When the control stick 146 is in the solid line position of FIG. 8, the pivoting vane is in its blocking position and the number four thrust generating means 50 is inoperative. When the operator moves the control stick 146 in the channel 148 to the phantom position 146', the vane will pivot to its open position and allow the number four thrust generating means 50 to generate thrust in the direction of arrow 66 in FIG. 2.

In like manner, control sticks 150 and 152 are movable in slots 154 and 156 to control the positioning of the pivoting vanes located in the conduits (FIG. 3) and 106 (FIG. 1) associated with the rear thrusters 102 and 104 respectively. That is, movement of the control sticks and 152 downwardly in FIG. 8 will rotate the associated pivoting vanes to their open position and allow the thrust generating means 102 and 104 to propel the craft in a rearward direction. In addition, the aforementioned control sticks 130 and 132 are movable and selectively positionable in slots I58 and 160 respectively to control the movement and positioning of the gates 88 and 89 associated with the collection chambers 34 and 36. Finally, a pair of throttles 162 and 164 are provided to control the output of the prime movers 72 and 73 respectively, and a wheel 166 is provided to control the aforementioned rudder 98.

It should be pointed out, and has been mentioned previously, that preferably the control sticks are linked to the various controlled devices by well-known protectively enclosed direct push pull cables the desired direct mechanical control. If desired, other techniques employing hydraulics and/or pneumatics may be employed to interconnect the control sticks with the respective operating devices.

Considering now FIG. 8 in conjunction with FIG. 2, should the operator desire to move the craft 12 laterally in the port direction (downwardly in FIG. 2), he simply moves control stick 134 and 138 in a port direction (that is to the left in FIG. 8) from their solid line positions to their phantom position 134' and 138' respectively. As noted previously, this will cause the number three thrust generating means and number two thrust generating means 48 and 46 respectively to generate thrust in a direction of arrows 60 and 62 thereby moving the craft laterally in the port direction. Similarly, should the operator desire to move the craft laterally in the starboard direction (upwardly in FIG. 2), he would move control sticks 142 and 146 to the right or in the starboard direction in FIG. 8 which in turn would permit number one thrust generating means and number four thrust generating means 44 and 50 respectively to generate thrust in the direction of arrows 64 and 66 respectively in FIG. 2 thereby moving the craft in the starboard direction.

It will be appreciated that this operation will be easily understood by the operator since the desired direction of lateral movement of the craft corresponds exactly to the necessary movement of the respective control sticks. If desired, arrowheads such as 168, 170, 172 and 174 can be imprinted on the control panel 22 to more definitely inform the operator of the results of the movements of the respective control sticks.

In like manner should the operator desire to cause the craft 10 to rotate in a clockwise direction about the turning axis 38 of FIG. 2, he merely moves control stick 142 to the right to its phantom line position 142' and control stick 138 to the left to its phantom position 138'. This causes the number one thrust generating means and the number two thrust generating means 44 and 46 respectively to generate clockwise moments in the direction of arrowheads 64 and 62 respectively of FIG. 2. If desired, this can be illustrated graphically on the control panel in FIG. 8 by the imprinting of arrowheads 176 and 178 and a clockwise arrowhead 180 all laid out about an imaginary turning axis designated by the circle or dot 38 on the console 22.

Similarly, should the operator desire to rotate the craft counterclockwise about the turning axis 38, he would move the control stick 134 of FIG. 8 to its phantom position 134' and the control stick 146 to its phantom position 146' of FIG. 8. This would permit the number three and number four thrust generating means 48 and 50 respectively to generate counterclockwise moments about the turning axis 38 in a direction of the thrust arrows 60 and 66 of FIG. 2. To illustrate this graphically, arrowheads 182, 184 and 186 may be imprinted on the control panel 22 in a different color then the aforementioned arrowheads 176, 178 and 180. Again it will be appreciated that this logical layout of the various control sticks makes it a relatively easy task even for unskilled personnel to control the rather sophisticated maneuvering capabilities of the craft of the instant invention.

In all of the above discussion, it will be appreciated that the various thrust generating means will become more effective as greater pressure head is developed in their respective conduits. This in turn depends of course upon the pressure being developed in the associated collection chambers 34 and 36 respectively. Accordingly, the operator can use the gates 88 and 89 respectively under the control of sticks 130 and 132 of FIG. 8 to preselectively close by any desired amount the exit openings of the respective collection chambers 34 and 36. The more the exit openings of the collection chambers are closed, the greater the pressure head developed in the associated collection chamber, and the more effective the associated thrust generating means will become when their associated pivoting vanes are moved to their open positions.

To complete maneuverability, especially at high speeds, the aforementioned rudder 98 is positioned at the rear of the craft on the imaginary longitudinal axis 40 of the craft. With respect to FIG. 7, the rudder assembly 188 comprises a pair of generally L-shaped brackets 190 and 192 secured by one leg thereof 194 and 196 respectively to a transverse member 198 defining the rear of the craft 10. A rudderpost block 2010 having a vertical passageway 202 therethrough is pivotally connected by axis 204 between the other legs 206 and 208 respectively of the L-shaped members 190 and 192. A pair of shear pins 210 (only one of which is visible in FIG. 7) also passes through the legs 208 and 208 into securement with the rudderpost block 200. A rudderpost 212 is freely rotatable within the aforementioned passageway 202 and carries at its end 214 thereof the rudder 98.

Under normal circumstances, the shear pins 210 (together with the axis 204) will maintain the rudderpost 212 in the vertical, operating position. Should the rudderpost 212 happen upon a fixed obstacle, such as a sandbar, the shear pins 210 will shear or break such that the entire rudderpost block 200, with the rudderpost 212 and rudder 98, can rotate about axis 204 to avoid damage to the rudder assembly.

Returning now to the consideration of the propulsor means 18 and 20 respectively, it should be initially pointed out that the propulsor means are identical in construction and accordingly only the propulsor means 20 illustrated in FIG. 3 will be described in detail. As noted previously, the propulsor means each include a detachable member 70, preferably a one-piece casting of aluminum. With reference to FIG. 6, the forward surface 216 of the member 70 is defined by an intumed flange 218 having a plurality of apertures 220 therethrough by which fastening means, preferably in the form of bolts (not shown), may be passed to join the detachable member 70 and hence the entire propulsor means to the rear of the craft. Such construction makes the entire propulsor means a removable module which can be easily attached to the craft during initial construction, and easily removed from the craft should replacement be necessary.

As also suggested in FIG. 6 and shown in FIG. 7, the detachable member 70 includes a generally forward hollow section 222 which is preferably filled with a buoyant material such as a solid foam.

As best seen perhaps in FIG. 1, the detachable member 70 also includes a flow channel 224 one end of which constitutes the aforedefined inlet opening 30 of the propulsor means while the opposite end 226 (see FIG. 3) constitutes an intake opening to the aforementioned propulsor housing 80. It is the output of the propulsor housing 80 which defines the aforementioned discharge opening 32 of the propulsor means 20.

The detachable member 70 also has secured thereto a pair of generally U-shaped frame member 228 and 230 between which are secured a plurality of struts 232 which cover the inlet opening 30 and thereby prevent the entrance of debris into the flow channel 224. Additionally, if desired, ap-

propriate screening may be secured between the struts 232 to provide additional protection. To provide access to the flow channel 224, the detachable member 70 includes a vertical passageway 234 (see FIG. 3 and 5) normally covered by a removable cover plate 236.

As also noted previously, the detachable member 70 terminates in a rearwardly extending upper portion 76 having the aforedeflned upper surface 74 and lower surface 78 thereof. Additionally, the rearwardly extending upper portion 76 includes a passageway 238 in which is positioned a clutch 240 preferably of the centrifugal type to interconnect the output shaft 242 of the prime mover 72 to the impeller drive shaft 244 to be described in greater detail with respect to FIG. 4.

As best seen in FIG. 5, circumferentially disposed about the passageway 238 are a plurality of through holes 246 through which a plurality of fastening elements 248 (only two of which are visible in FIG. 3) may pass to secure the propulsor housing to the undersurface 78 of the rearwardly extending portion 76. Additionally, and as seen in FIG. 5, the upper surface 74 of the rearwardly extending portion 76 of the detachable member 70 includes a plurality of boltholes 250 into which bolts 252 may pass in joining the mounting flange 254 of the prime mover 72 to the upper surface 74. As best seen in FIG. 3, the mounting flange 254 also includes a plurality of countersunk openings 256 which receive the heads of the aforementioned fastening elements 248 when the prime mover is secured to the upper surface 74 by the bolts 252.

From the above, it will be appreciated that the detachable member 70 is a multifunction member which: allows the propulsor means to be a modular unit; is partially hollow for the reception of buoyant material; defines a flow channel 224; defines a vertical passageway 234 permitting access to the flow channel 224; supports a strut arrangement which prevents debris from entering the flow channel; provides the mounting surface for the propulsor housing 80; and provides a housing 238 for the clutch 240.

Turning to FIG. 4, the impeller 82 is defined by blades 258 secured to a hub 260 rotatable by means of bearings 262 about a fixed shaft 264. A right angle drive established by the cooperation of gears 266 and 268 is provided to interconnect the impeller drive shaft 244 and the impeller 82 which thereby functions in an obvious manner as an axial flow pump,

The opposite end 270 of the impeller drive shaft 244 is rotatably supported by bearings 272 in an aperture 274 provided in the upper surface 276 of the propulsor housing 80. An annular retaining ring 278 is secured to the propulsor housing 80 and retains the bearing 272 in its seated position. As seen in FIG. 4, the inner annulus 280 of the retaining ring 278 is raised with respect to the remainder of the annular retaining ring and together with a slinger disc 282 secured to the impeller drive shaft 244 functions to prevent water from reaching the bearing 272.

It will be appreciated that in assembling the propulsor means 20, the propulsor housing 80 is slipped under the lower surface 78 of the rearwardly extending portion 76 of the detachable member 70 and secured thereto by the aforementioned members 248. In assembly, the propulsor housing would include the impeller drive shaft 244 protruding from the aperture 274 and also one-half of the clutch 240. Next the prime mover 72 with its mounting flange 254 would be positioned on the upper surface 74 with its countersunk holes 256 receiving the heads of the fastening members 248, bolts 252 being used to secure the prime mover in place. In assembly, the prime mover would include its output shaft 242 and the other half of the clutch arrangement of the clutch assembly 240. Finally, the entire modular propulsor means would be secured to the rear of the craft.

As best illustrated in FIG. 4, the diameter D of the outlet end of the propulsor housing 80 (which defines the discharge opening 32 of the propulsor means), is relatively large, and in accordance with the invention, provides a rather slow discharge from the propulsor means thereby producing maximum efficiency at the slow speeds for which the craft of the instant invention is designed. For example, for a maximum forward speed of approximately 10 miles per hour, the discharge diameter is chosen to produce the relatively slow discharge velocity of approximately 20 miles per hour. This ratio of approximately 2:1 is preferably maintained regardless of the chosen maximum forward speed. To maintain the desired discharge velocity, it has been found that the diameter of the discharge opening 32 should be in the range of O.l50.35 inches per horsepower of the prime mover when the prime mover is above 30 horsepower, and in the range of 0.350.5 inches per horsepower of the prime mover when the prime mover is below 30 horsepower.

It should be noted in passing that the particular prime movers 72 and 73 are of no particular importance to the instant invention. In the preferred embodiment, apair of vertical, air-cooled, rotary piston engines of the Wankel type are employed. For the sake of drawing clarity, such items as the carburetor, muffler, exhaust system, fuel tank, etc., have not been illustrated.

Although this invention has been described with respect to its preferred embodiments, it should be understood that many variations and modifications will now be obvious to those skilled in the art, and it is preferred, therefore, that the scope of the invention be limited, not by the specific disclosure herein, only by the appended claims.

What is claimed is:

l. A watercraft comprising:

a body member having a turning axis defined by the intersection of a longitudinal axis and a horizontal axis; first propulsor means secured to said body member for accepting water at an inlet opening thereof and discharging water at a higher pressure at a discharge opening thereof;

second propulsor means secured to said body member for accepting water at an inlet opening thereof and discharging water at a higher pressure at a discharge opening thereof;

first thrust generating means in fluid communication with said discharge opening of said second propulsor means for generating thrust in a first direction about said turning axis;

second thrust generating means in fluid communication with said discharge opening of said first propulsor means for generating thrust in the first direction about said turning axis;

third thrust generating means in fluid communication with said discharge opening of said first propulsor means for generating thrust in said second direction about said turning axis;

fourth thrust generating means in fluid communication with said discharge opening of said second propulsor means for generating thrust in said second direction about said turning axis;

maneuverability control means on said body member for selectively establishing and nonestablishing the fluid communication between said first and second propulsor means and said first, second, third, and fourth thrust generating means.

2. The watercraft of claim 1 wherein said longitudinal axis and said horizontal axis define first, second, third and four imaginary quadrants disposed consecutively about said turning axis in a clockwise direction;

said first thrust generating means being located in said fourth quadrant;

said second thrust generating means being located in said second quadrant;

said third thrust generating means being located in said first quadrant; and said fourth thrust generating means being located in said third quadrant.

3. The watercraft of claim 1 and further including first collection chamber means in fluid communication with the discharge opening of said first propulsor means for collecting water discharged by said first propulsor means; and

second collection chamber means in fluid communication with the discharge opening of said second propulsor means for collecting water discharged by said second propulsor means. means;

4. The watercraft of claim 3 wherein said first collection chamber means includes an exit opening for permitting water to exit therefrom, and said second collection chamber means includes an exit opening for permitting water to exit therefrom; and

further including first gate means secured to said first collection chamber means and movable between a first posi' tion in which the exit opening thereof is open, and a second position in which the exit opening of said first collection chamber is closed; and

second gate means secured to said second collection chamber means and movable between a first position in which the exit opening thereof is open, and a second position in which the exit opening of said second collection chamber means is closed.

5. The watercraft of claim 4 and further including gate control means on said body member for selectively moving and fixing said first and second gate means between their respective first and second positions;

movement of the respective first and second gate means towards their respective second positions causing their respective first and second collection chamber means to accumulate water at an increasingly higher pressure.

6. The watercraft of claim 5 wherein the fluid communication between said discharge openings of said first and second propulsor means and the respective ones of said first, second, third, and fourth thrust generating means is established by a plurality of fluid carrying conduits;

a first conduit connected at one end there to said first collection chamber means and at its other end thereof to said third thrust generating means;

a second conduit connected at one end thereof to said first collection chamber means and at its other end thereof to said second thrust generating means;

a third conduit connected at one end thereof to said second collection chamber means and at its other end thereof to said first thrust generating means;

and a fourth conduit connected at one end thereof to said second collection chamber means and at its other end to said fourth thrust generating means.

7. The watercraft of claim 6 wherein said maneuverability control means includes:

first, second, third and fourth pivoting vane means disposed in respective ones of said first, second, third and fourth conduits, each of said pivoting vane means being pivotally movable between a first position which blocks its respective conduit to prevent waterflow therethrough, and a second position which opens its respective conduit to permit waterflow therethrough; and

manually operable maneuverability control stick means operatively connected to said plurality of pivoting vane means for moving selected ones of said vanes between their first and second positions.

8. The watercraft of claim 7 and further including fifth thrust generating means in fluid communication with said first collection chamber means for generating thrust on said body member in a rearward direction with respect to the forward direction of travel of said body member;

and sixth thrust generating means in fluid communication with said second collection chamber means for generating thrust on said body member in a rearward direction with respect to the forward direction of travel of said body member;

and reverse control means on said body member for selectively establishing and nonestablishing the fluid communication between said first and second collection chamber means and their associated fifth and sixth thrust generating means.

9. The watercraft of claim 8 wherein the fluid communication between said first collection chamber means and said fifth thrust generating means is established by a fifth conduit connected at one end thereof to said first collection chamber means and at its other end thereof to said fifth thrust generating means; and

the fluid communication between said second collection chamber means and said sixth thrust generating means is established by a sixth conduit connected at one end thereof to said second collection chamber means at its other end thereof to said sixth thrust generating means; and

said reverse control means includes pivoting vane means disposed in each of said fifth and sixth conduits and pivotally movable between a first position which blocks its respective conduit and a second position opens its respective conduit; and

manuable operable reverse control stick means operatively connected to said pivoting vane in said fifth and sixth conduits for moving them between their first and second positions.

10. The watercraft of claim 7 and further including a control panel;

and wherein said manually operable maneuverability control stick means comprises:

first, second, third and fourth control sticks operatively connected to said first, second, third and fourth pivoting vane means respectively;

said first, second, third and fourth control sticks being movable on said control panel between first positions which correspond to their respective pivoting vane means being in their first, blocking position, and second positions which correspond to their respective pivoting vane means being in their second, open position;

said first and fourth control sticks being grouped together and located on the starboard side of said control panel and movable between their first and second positions in a starboard direction;

whereby simultaneous movement of said first and fourth control sticks in the starboard direction toward their second positions will cause said first and fourth thrust generating means to operate and move said body member in said starboard direction with respect to the longitudinal axis of said body member;

said third and second control sticks being grouped together and located on the port side of said control panel and movable between their first and second positions in a port direction;

whereby simultaneous movement of said third and second control sticks in the port direction toward their second positions will cause said third and second thrust generating means to operate and move said body member in said port direction with respect to said longitudinal axis of said body member.

11. The watercraft of claim and wherein said first and second propulsor means are secured to the rear of said body member on opposite sides of said longitudinal axis thereof;

said first and second collection chamber means are secured to said first and second propulsor means respectively on the rear side thereof; and said exit openings of said first and second collection chamber means face the stern of said body member;

whereby the movement of said first and second gate means in selectively covering said exit openings of said first and second collection chamber means may be utilized to control the amount of forward thrust generated on said body member by said exit openings.

12. The watercraft of claim 1 wherein said first and second propulsor means are secured to the rear of said body member on opposite sides of said longitudinal axis thereof; and

further including a rudder assembly secured to the rear of said body member and disposed on said longitudinal axis thereof;

said rudder assembly comprising:

first and second generally L-shaped brackets secured to the rear of said body member;

a rudderpost supporting member pivotally connected to said brackets, said supporting member being connected at a second location thereof to said brackets by breakable pins, said supporting member having an aperture therethrough;

a rudderpost rotatably positioned in said aperture of said supporting member; and

a rudder fixedly secured to the lower end of said rudderpost;

whereby said shear pins will break and said rudderpost block will pivotally rotate with respect to said brackets should said rudderpost encounter a relatively rearward force greater than the predetermined strength of said shear pins.

13. The watercraft of claim 3 wherein each of said first and second propulsor means comprises:

a detachable member removably secured to the rear of said body member, said detachable member having a flow channel therein, one end of said flow channel defining said inlet opening of said propulsor means;

a propulsor housing secured to said detachable member, said propulsor housing having an intake opening in fluid communication with the opposite end of said flow channel, and an outlet opening which defines said discharge opening of said propulsor means;

an impeller disposed in said propulsor housing intermediate said intake opening and said discharge opening; and

motive means operatively connected to said impeller for rotating said impeller.

14. The watercraft of claim 13 wherein said detachable member further includes a hollow section; and

further including buoyant material disposed in said hollow section.

15. The watercraft of claim 14 and further including screening means secured to said detachable member and covering said inlet opening for preventing debris from entering said flow channel.

16. The watercraft of claim 13 and further including screening means secured to said detachable member and covering said inlet opening for preventing debris from entering said flow channel.

17. The watercraft of claim 14 wherein said detachable member includes a rearwardly extending upper portion having an upper and lower surface, said propulsor housing being secured to said under surface and said motive means secured to said upper surface.

18. The watercraft of claim 13 wherein said detachable member includes a rearwardly extending upper portion having an upper and lower surface, said propulsor housing being secured to said under surface and said motive means secured to said upper surface.

19. The watercraft of claim 18 wherein said upper portion includes a passageway therethrough; and

said motive means includes a prime mover having an output shaft which is operatively connected through said elon gated passageway to said impeller.

20. The watercraft of claim 19 wherein said upper portion of said detachable member includes a plurality of through holes disposed circumferentially about said passageway and further including a plurality of fastening elements passing through said holes for securing said propulsor housing to counter-sunk said under surface of said rearwardly extending upper portion.

21. The watercraft of claim 20 wherein said prime mover includes a mounting flange by which said prime mover is secured to said upper surface of said rearwardly extending upper portion of said detachable member, said mounting flange having a plurality of counter-sunk openings which receive the heads of said fastening elements when said prime mover is secured to said upper surface.

22. The watercraft of claim 19 and further including an impeller drive shaft, one end of which is in driving relationship with said impeller and the opposite end of which extends through an aperture in said propulsor housing into said passageway of said upper portion of said detachable member;

and wherein the operative connection between said output shaft of said prime mover and said impeller includes clutch means positioned in said passageway of said upper portion of said detachable member for selectively connecting said output shaft of said prime mover to said opposite end of said impeller drive shaft.

23. The watercraft of claim 22 and further including:

bearing means positioned in the aperture of said propulsor housing for rotatably supporting said impeller drive shaft therein;

annular retaining ring means secured to said propulsor housing for retaining said bearing means in said aperture; the inner annulus of said annular retaining ring means being raised with respect to the remainder of said annular retaining ring means;

a disk member fixedly secured to said impeller drive shaft slightly above said inner annulus for slinging water away from said aperture.

24. The watercraft of claim 14 wherein said detachable member includes an intumed flange on a forward surface thereof, said flange having a plurality of apparatus through which fastening means may pass to secure said detachable member to said body member.

25. The watercraft of claim 18 wherein said detachable member is of integral construction.

26. The watercraft of claim 25 wherein said detachable member is a casting.

27. The watercraft of claim 13 wherein said discharge opening is of predetermined diameter with respect to the output power of said motive means to thereby establish a predetermined discharge velocity with respect to the maximum forward speed of said watercraft.

28. The watercraft of claim 27 wherein said predetermined discharge velocity is approximately twice the desired maximum forward speed of said watercraft.

29. The watercraft of claim 27 wherein the diameter of said discharge opening lies in the range of 0.15-0.35 inches per horsepower of output of said motive means for motive means producing above 30 horsepower.

30. The watercraft of claim 29 wherein the diameter of said discharge opening lies in the range of 035-05 inches per horsepower of output of said motive means for motive means producing below 30 horsepower.

31. The watercraft of claim 13 wherein said detachable member includes an access channelway one end of which is in communication with said flow channel, and further including a cover member removably secured to said detachable member in closing relationship with respect to the opposite end of the said access channelway.

32. Propulsor means for use on a buoyant body member; said propulsor means comprising:

a detachable member removably secured to the rear of said body member, said detachable member having a flow channel therein, one end of said flow channel defining said inlet opening of said propulsor means;

a propulsor housing secured to said detachable member, said propulsor housing having an intake opening in fluid communication with the opposite end of said flow channel, and an outlet opening which defines said discharge opening of said propulsor means;

an impeller disposed in said propulsor housing intermediate said intake opening and said discharge opening; and

motive means operatively connected to said impeller for rotating said impeller wherein said detachable member further includes a hollow section; and

further including buoyant material disposed in said hollow section wherein said detachable member includes a rearwardly extending upper portion having an upper and lower surface, said propulsor housing being secured to said under surface and said motive means secured to said upper surface.

33. Propulsor means for use on a buoyant body member; said propulsor means comprising;

a detachable member removably secured to the rear of said body member, said detachable member having a flow channel therein, one end of said flow channel defining said inlet opening of said propulsor means;

a propulsor housing secured to said detachable member, said propulsor housing having an intake opening in fluid communication with the opposite end of said flow channel, and an outlet opening which defines said discharge opening of said propulsor means;

an impeller disposed in said propulsor housing intermediate said intake opening and said discharge opening; and

motive means operatively connected to said impeller for rotating said impeller; wherein said detachable member includes a rearwardly extending upper portion having an upper and lower surface, said propulsor housing being secured to said under surface and said motive means secured to said upper surface.

34. The propulsor means of claim 33 wherein said upper portion includes a passageway therethrough; and

said motive means includes a prime mover having an output shaft which is operatively connected through said elongated passageway to said impeller.

35. The propulsor means of claim 34 wherein said upper portion of said detachable member includes a plurality of through holes disposed circumferentially about said passageway and further including a plurality of fastening elements passing through said holes for securing said propulsor housing to the said under surface of said rearwardly extending upper portion.

36. The propulsor means of claim 35 wherein said prime mover includes a mounting flange by which said prime mover is secured to said upper surface of said rearwardly extending upper portion of said detachable member, said mounting flange having a plurality of counter-sunk openings which receive the heads of said fastening elements when said prime mover is secured to said upper surface.

37. The propulsor means of claim 34 and further including an impeller drive shaft, one end of which is in driving relationship with said impeller and the opposite end of which extends through an aperture in said propulsor housing into said passageway of said upper portion of said detachable member; and wherein the operative connection between said output shaft of said prime mover and said impeller includes clutch means positioned in said passageway of said upper portion of said detachable member for selectively connecting said output shaft of said prime mover to said opposite end of said impeller 0 drive shaft.

38. The propulsor means of claim 37 and further including:

bearing means positioned in the apertureof said propulsor housing for rotatably supporting said impeller drive shaft therein;

annular retaining ring means secured to said propulsor housing for retaining said bearing means in said aperture; the inner annulus of said annular retaining ring means being raised with respect to the remainder of said annular retaining ring means;

a disk member fixedly secured to said impeller drive shaft slightly above said inner annulus for slinging water away from said aperture.

39. Propulsor means for use on a buoyant body member;

said propulsor means comprising:

a detachable member removably secured to the rear of said body member, said detachable member having a flow channel therein, one end of said flow channel defining said inlet opening of said propulsor means;

a propulsor housing secured to said detachable member, said propulsor housing having an intake opening in fluid communication with the opposite end of said flow channel, and an outlet opening which defines said discharge opening of said propulsor means;

an impeller disposed in said propulsor housing intermediate said intake opening and said discharge opening; and

motive means operatively connected to said impeller for rotating said impeller wherein said detachable member further includes a hollow section; and

further including buoyant material disposed in said hollow section; wherein said detachable member includes an inturned flange on a forward surface thereof, said flange having a plurality of apertures through which fastening means may pass to secure said detachable member to said body member.

40. The propulsor means of claim 33 wherein said detachable member is of integral construction.

41. The propulsor means of claim 40 wherein said detachable member is a casting.

42. Propulsor means for use on a buoyant body member; said propulsor means comprising:

a detachable member removably secured to the rear of said body member, said detachable member having a flow channel therein, one end of said flow channel defining said inlet opening of said propulsor means;

a propulsor housing secured to said detachable member, said propulsor housing having an intake opening in fluid communication with the opposite end of said flow channel, and an outlet opening which defines said discharge opening ofsaid propulsor means;

an impeller disposed in said propulsor housing intermediate said intake opening and said discharge opening;

motive means operatively connected to said impeller for rotating said impeller; wherein said discharge opening is of predetermined diameter with respect to the output power of said motive means to thereby establish a predetermined discharge velocity with respect to the maximum forward speed of said water craft; wherein said predetermined discharge velocity is approximately twice the desired maximum forward speed of said water craft; and wherein said detachable member includes a rearwardly extending upper portion having an upper and lower surface, said propulsor housing being secured to said under surface and said motive means secured to said upper surface.

43. The propulsor means of claim 42 wherein the diameter of said discharge opening lies in the range of 0.15-0.35 inches per horsepower of output of said motive means for motive means producing above 30 horsepower.

44. The propulsor means of claim 43 wherein the diameter of said discharge opening lies in the range of 0.350.5 inches per horsepower of output of said motive means for motive means producing above 30 horsepower.

45. Propulsor means for use on a buoyant body member; said propulsor means comprising:

a detachable member removably secured to the rear of said body member, said detachable member having a flow channel therein, one end of said flow channel defining said inlet opening of said propulsor means;

a propulsor housing secured to said detachable member, said propulsor housing having an intake opening in fluid communication with the opposite end of said flow channel, and an outlet opening which defines said discharge opening of said propulsor means;

an impeller disposed in said propulsor housing intermediate said intake opening and said discharge opening; and

motive means operatively connected to said impeller for rotating said impeller; wherein said detachable member includes an access channelway one end of which is in communication with said flow channel, and further including a cover member removably secured to said detachable member in closing relationship with respect to the opposite end of the said access channelway.

46. An oil slick recovery system comprising:

a watercraft of the catamaran type having first and second spaced apart hulls joined by a deck, said deck having an opening intermediate said hulls; oil recovery means operatively positioned with respect to said opening to recover oil from the water in which said watercraft is floating;

first and second propulsor means secured to the rear ends of said first and second hulls respectively for accepting water at an inlet opening and discharging water at a higher pressure at a discharge opening thereof; and

a maneuverability system responsive to said first and second propulsor means for maneuvering said watercraft wherein said oil recovery means includes a roller positionable through said opening into said water, said roller having an absorbent covering thereabout; driving means for rotating said roller in the water; and

pressure roller means engageable with said roller for squeezing the oil from absorbent covering; wherein said maneuverability system includes:

first thrust generating means in fluid communication with said discharge opening of said second propulsor means for generating thrust in a first direction about said turning axis;

second thrust generating means in fluid communication with said discharge opening of said first propulsor means for generating thrust in a first'direction, about said turning axis;

third thrust generating means in fluid communication with said discharge opening of said first propulsor means for generating thrust in said second direction about said turn ing axis;

fourth thrust generating means in fluid communication with said discharge opening of said second propulsor means for generating thrust in said second direction about said turning axis; and

maneuverability control means on said body member for selectively establishing and nonestablishing the fluid communication between said first and second propulsor means and said first, second, third, and fourth thrust generating means.

47. The oil slick recovery system of claim 46 and further including first collection chamber means in fluid communication with the discharge opening of said first propulsor means for collecting water discharged by said first propulsor means; and

second collection chamber means in fluid communication with the discharge opening of said second propulsor means for collecting water discharged by said second propulsor means.

48. The oil slick recovery system of claim 47 wherein said first collection chamber means includes an exit opening for permitting water to exit therefrom, and said second collection chamber means includes an exit opening for permitting water to exit therefrom; and

further including first gate means secured to said first collection chamber means and movable between a first position in which the exit opening thereof is open, and a second position in which the exit opening of said first collection chamber is closed; and

second gate means secured to said second collection chamber means and movable between a first position in which the exit opening of said second collection chamber means is closed.

49. The oil slick recovery system of claim 48 and further including gate control means on said body member for selectively moving said first and second gate means between their respective first and second positions;

movement of the respective first and second gate means towards their respective second positions causing their respective first and second collection chamber means to accumulate water at an increasingly higher pressure.

50. The oil slick recovery system of claim 49 wherein the fluid communication between said discharge openings of said first and second propulsor means and the respective ones of said first, second, third and fourth thrust generating means is established by a plurality of fluid carrying conduits;

a first conduit connected at one end there to said first collection chamber means and at its other end thereof to said first thrust generating means;

a second conduit connected at one end thereof to said first collection chamber means and at its other end thereof to said second thrust generatingmeans;

a third conduit connected at one end thereof to said second collection chamber means and at its other end thereof to said third thrust generating means;

and a fourth conduit connected at one end thereof to said second collection chamber means and at its other end to said fourth thrust generating means.

51. The oil slick recovery system of claim 50 wherein said maneuverability control means includes:

first, second, third and fourth pivoting vane means disposed in respective ones of said first, second, third and fourth conduits, each of said pivoting vane means being pivotally movable between a first position which blocks its respective conduit to prevent water flow therethrough, and a second position which opens its respective conduit to permit water flow therethrough; and

manually operable maneuverability control stick means operatively connected to said plurality of pivoting vane means for moving selected ones of said vanes between their first and second positions.

52. The oil slick recovery system of claim 51 and further including fifth thrust generating means in fluid communication with said first collection chamber means for generating thrust on said body member in a rearward direction with respect to the forward direction of travel of said body member;

and sixth thrust generating means in fluid communication with said second collection chamber means for generating thrust on said body member in a rearward direction with respect to the forward direction of travel of said body member;

and reverse control means on said body member for selectively establishing and nonestablishing the fluid communication between said first and second collection chamber means and their associated fifth and sixth thrust generating means.

53. The oil slick recovery system of claim 52 and further including a control panel;

and wherein said manually operable maneuverability control stick means comprises:

first, second, third and fourth control sticks operatively connected to said first, second, third and fourth pivoting vane means respectively;

said first, second, third and fourth control sticks being movable on said control panel between first positions which correspond to their respective pivoting vane means being in their first, blocking position, and second positions which correspond to their respective pivoting vane means being in their second, open position;

said first and fourth control sticks being grouped together and located on the starboard side of said control panel and movable between their first and second positions in a starboard direction;

whereby simultaneous movement of said first and fourth control sticks in the starboard direction toward their second positions will cause said first and fourth thrust generating means to operate and move said body member in said starboard direction with respect to the longitudinal axis of said body member;

said third and second control sticks being grouped together and located on the port side of said control panel and movable between their first and second positions in a port direction;

whereby simultaneous movement of said third and second control sticks in the port direction toward their second positions will cause said third and second thrust generating means to operate and move said body member in said port direction with respect to said longitudinal axis of said body member.

547 The oil slick recovery system of claim 49 wherein said first and second propulsor means are secured to the rear of said body member on opposite sides of said longitudinal axis thereof;

said first and second collection chamber means are secured to said first and second propulsor means respectively on the rear side thereof; and

said exit openings of said first and second collection chamber means face the stern of said body member;

whereby the movement of said first and second gate means in selectively covering said exit openings of said first and second collection chamber means may be utilized to control the amount of forward thrust generated on said body member by said exit openings.

55. The oil slick recovery system of claim 47 wherein each of said first and second propulsor means comprises:

a detachable member removably secured to the rear of said body member, said detachable member having a flow channel therein, one end of said flow channel defining said inlet opening of said propulsor means;

a propulsor housing secured to said detachable member, said propulsor housing having an intake opening in fluid communication with the opposite end of said flow channel, and an outlet opening which defines said discharge opening of said propulsor means;

an impeller disposed in said propulsor housing intermediate said intake opening and said discharge opening; and

motive means operatively connected to said impeller for rotating said impeller.

56. The oil slick recovery system of claim 55 wherein said detachable member further includes a hollow section; and

further including buoyant material disposed in said hollow section.

57. The oil slick recovery system of claim 56 and further including screening means secured to said detachable member and covering said inlet opening for preventing debris from entering said flow channel.

58. The oil slick recovery system of claim 55 wherein said detachable member includes a rearwardly extending upper portion having an upper and lower surface, said propulsor housing being secured to said under surface and said motive means secured to said upper surface.

59. The oil slick recovery system of claim 58 wherein said upper portion includes a passageway therethrough; and

said motive means includes a prime mover having an output shaft which is operatively connected through said elongated passageway to said impeller.

60. The oil slick recovery system of claim 59 wherein said upper portion of said detachable member includes a plurality of through holes disposed circumferentially about said passageway and further including a plurality of fastening elements passing through said holes for securing said propulsor housing to the said under surface of said rearwardly extending upper portion.

61. The oil slick recovery system of claim 60 wherein said prime mover includes a mounting flange by which said prime mover is secured to said upper surface of said rearwardly extending upper portion of said detachable member, said mounting flange having a plurality of countersunk openings which receive the heads of said fastening elements when said prime mover is secured to said upper surface.

62. The oil slick recovery system of claim 61 and further including an impeller drive shaft, one end of which is in driving relationship with said impeller and the opposite end of which extends through an aperture in said propulsor housing into said passageway of said upper portion of said detachable member; and wherein the operative connection between said output shaft of said prime mover and said impeller includes clutch means positioned in said passageway of said upper portion of said detachable member for selectively connecting said output shaft of said prime mover to said opposite end of said impeller drive shaft.

63. The oil slick recovery system of claim 62 and further including:

bearing means positioned in the aperture of said propulsor housing for rotatably supporting said impeller drive shaft therein;

annular retaining ring means secured to said propulsor housing for retaining said bearing means in said aperture; the inner annulus of said annular retaining ring means being raised with respect to the remainder of said annular retaining ring means;

a disk member fixedly secured to said impeller drive shaft slightly above said inner annulus for slinging water away from said aperture.

64. An oil slick recovery system comprising:

a watercraft of the catamaran type having first and second spaced apart hulls joined by a deck, said deck having an opening intermediate said hulls;

oil recovery means operatively positioned with respect to said opening to recover oil from the water in which said water craft is floating;

first and second propulsor means secured to the rear ends of said first and second hulls respectively for accepting water at an inlet opening and discharging water at a higher pressure at a discharge opening thereof; and

a maneuverability system responsive to said first and second propulsor means for maneuvering said watercraft wherein each of said first and second propulsor means each comprise:

a detachable member removably secured to the rear of said body member, said detachable member having a flow channel therein, one end of said flow channel defining said inlet opening of said propulsor means;

a propulsor housing secured to said detachable member, said propulsor housing having an intake opening in fluid communication with the opposite end of said flow channel, and an outlet opening which defines said discharge opening of said propulsor means;

an impeller disposed in said propulsor housing intermediate said intake opening and said discharge opening; and

motive means operatively connected to said impeller for rotating said impeller; wherein said detachable member includes a rearwardly extending upper portion having an upper and lower surface, said propulsor housing being secured to said under surface and said motive means secured to said upper surface. 

1. A watercraft comprising: a body member having a turning axis defined by the intersection of a longitudinal axis and a horizontal axis; first propulsor means secured to said body member for accepting water at an inlet opening thereof and discharging water at a higher pressure at a discharge opening thereof; second propulsor means secured to said body member for accepting water at an inlet opening thereof and discharging water at a higher pressure at a discharge opening thereof; first thrust generating means in fluid communication with said discharge opening of said second propulsor means for generating thrust in a first direction about said turning axis; second thrust generating means in fluid communication with said discharge opening of said first propulsor means for generating thrust in the first direction about said turning axis; third thrust generating means in fluid communication with said discharge opening of said first propulsor means for generating thrust in said second direction about said turning axis; fourth thrust generating means in fluid communication with said discharge opening of said second propulsor means for generating thrust in said second direction about said turning axis; maneuverability control means on said body member for selectively establishing and nonestablishing the fluid communication between said first and second propulsor means and said first, second, third, and fourth thrust generatinG means.
 2. The watercraft of claim 1 wherein said longitudinal axis and said horizontal axis define first, second, third and four imaginary quadrants disposed consecutively about said turning axis in a clockwise direction; said first thrust generating means being located in said fourth quadrant; said second thrust generating means being located in said second quadrant; said third thrust generating means being located in said first quadrant; and said fourth thrust generating means being located in said third quadrant.
 3. The watercraft of claim 1 and further including first collection chamber means in fluid communication with the discharge opening of said first propulsor means for collecting water discharged by said first propulsor means; and second collection chamber means in fluid communication with the discharge opening of said second propulsor means for collecting water discharged by said second propulsor means. means;
 4. The watercraft of claim 3 wherein said first collection chamber means includes an exit opening for permitting water to exit therefrom, and said second collection chamber means includes an exit opening for permitting water to exit therefrom; and further including first gate means secured to said first collection chamber means and movable between a first position in which the exit opening thereof is open, and a second position in which the exit opening of said first collection chamber is closed; and second gate means secured to said second collection chamber means and movable between a first position in which the exit opening thereof is open, and a second position in which the exit opening of said second collection chamber means is closed.
 5. The watercraft of claim 4 and further including gate control means on said body member for selectively moving and fixing said first and second gate means between their respective first and second positions; movement of the respective first and second gate means towards their respective second positions causing their respective first and second collection chamber means to accumulate water at an increasingly higher pressure.
 6. The watercraft of claim 5 wherein the fluid communication between said discharge openings of said first and second propulsor means and the respective ones of said first, second, third, and fourth thrust generating means is established by a plurality of fluid carrying conduits; a first conduit connected at one end there to said first collection chamber means and at its other end thereof to said third thrust generating means; a second conduit connected at one end thereof to said first collection chamber means and at its other end thereof to said second thrust generating means; a third conduit connected at one end thereof to said second collection chamber means and at its other end thereof to said first thrust generating means; and a fourth conduit connected at one end thereof to said second collection chamber means and at its other end to said fourth thrust generating means.
 7. The watercraft of claim 6 wherein said maneuverability control means includes: first, second, third and fourth pivoting vane means disposed in respective ones of said first, second, third and fourth conduits, each of said pivoting vane means being pivotally movable between a first position which blocks its respective conduit to prevent waterflow therethrough, and a second position which opens its respective conduit to permit waterflow therethrough; and manually operable maneuverability control stick means operatively connected to said plurality of pivoting vane means for moving selected ones of said vanes between their first and second positions.
 8. The watercraft of claim 7 and further including fifth thrust generating means in fluid communication with said first collection chamber means for generating thrust on said body member in a rearward direction with respect to the forward direction of travel of said body member; and sixtH thrust generating means in fluid communication with said second collection chamber means for generating thrust on said body member in a rearward direction with respect to the forward direction of travel of said body member; and reverse control means on said body member for selectively establishing and nonestablishing the fluid communication between said first and second collection chamber means and their associated fifth and sixth thrust generating means.
 9. The watercraft of claim 8 wherein the fluid communication between said first collection chamber means and said fifth thrust generating means is established by a fifth conduit connected at one end thereof to said first collection chamber means and at its other end thereof to said fifth thrust generating means; and the fluid communication between said second collection chamber means and said sixth thrust generating means is established by a sixth conduit connected at one end thereof to said second collection chamber means at its other end thereof to said sixth thrust generating means; and said reverse control means includes pivoting vane means disposed in each of said fifth and sixth conduits and pivotally movable between a first position which blocks its respective conduit and a second position opens its respective conduit; and manuable operable reverse control stick means operatively connected to said pivoting vane in said fifth and sixth conduits for moving them between their first and second positions.
 10. The watercraft of claim 7 and further including a control panel; and wherein said manually operable maneuverability control stick means comprises: first, second, third and fourth control sticks operatively connected to said first, second, third and fourth pivoting vane means respectively; said first, second, third and fourth control sticks being movable on said control panel between first positions which correspond to their respective pivoting vane means being in their first, blocking position, and second positions which correspond to their respective pivoting vane means being in their second, open position; said first and fourth control sticks being grouped together and located on the starboard side of said control panel and movable between their first and second positions in a starboard direction; whereby simultaneous movement of said first and fourth control sticks in the starboard direction toward their second positions will cause said first and fourth thrust generating means to operate and move said body member in said starboard direction with respect to the longitudinal axis of said body member; said third and second control sticks being grouped together and located on the port side of said control panel and movable between their first and second positions in a port direction; whereby simultaneous movement of said third and second control sticks in the port direction toward their second positions will cause said third and second thrust generating means to operate and move said body member in said port direction with respect to said longitudinal axis of said body member.
 11. The watercraft of claim 5 and wherein said first and second propulsor means are secured to the rear of said body member on opposite sides of said longitudinal axis thereof; said first and second collection chamber means are secured to said first and second propulsor means respectively on the rear side thereof; and said exit openings of said first and second collection chamber means face the stern of said body member; whereby the movement of said first and second gate means in selectively covering said exit openings of said first and second collection chamber means may be utilized to control the amount of forward thrust generated on said body member by said exit openings.
 12. The watercraft of claim 1 wherein said first and second propulsor means are secured to the rear of said body member on opposite sides of said longitudinal axis thereof; and further iNcluding a rudder assembly secured to the rear of said body member and disposed on said longitudinal axis thereof; said rudder assembly comprising: first and second generally L-shaped brackets secured to the rear of said body member; a rudderpost supporting member pivotally connected to said brackets, said supporting member being connected at a second location thereof to said brackets by breakable pins, said supporting member having an aperture therethrough; a rudderpost rotatably positioned in said aperture of said supporting member; and a rudder fixedly secured to the lower end of said rudderpost; whereby said shear pins will break and said rudderpost block will pivotally rotate with respect to said brackets should said rudderpost encounter a relatively rearward force greater than the predetermined strength of said shear pins.
 13. The watercraft of claim 3 wherein each of said first and second propulsor means comprises: a detachable member removably secured to the rear of said body member, said detachable member having a flow channel therein, one end of said flow channel defining said inlet opening of said propulsor means; a propulsor housing secured to said detachable member, said propulsor housing having an intake opening in fluid communication with the opposite end of said flow channel, and an outlet opening which defines said discharge opening of said propulsor means; an impeller disposed in said propulsor housing intermediate said intake opening and said discharge opening; and motive means operatively connected to said impeller for rotating said impeller.
 14. The watercraft of claim 13 wherein said detachable member further includes a hollow section; and further including buoyant material disposed in said hollow section.
 15. The watercraft of claim 14 and further including screening means secured to said detachable member and covering said inlet opening for preventing debris from entering said flow channel.
 16. The watercraft of claim 13 and further including screening means secured to said detachable member and covering said inlet opening for preventing debris from entering said flow channel.
 17. The watercraft of claim 14 wherein said detachable member includes a rearwardly extending upper portion having an upper and lower surface, said propulsor housing being secured to said under surface and said motive means secured to said upper surface.
 18. The watercraft of claim 13 wherein said detachable member includes a rearwardly extending upper portion having an upper and lower surface, said propulsor housing being secured to said under surface and said motive means secured to said upper surface.
 19. The watercraft of claim 18 wherein said upper portion includes a passageway therethrough; and said motive means includes a prime mover having an output shaft which is operatively connected through said elongated passageway to said impeller.
 20. The watercraft of claim 19 wherein said upper portion of said detachable member includes a plurality of through holes disposed circumferentially about said passageway and further including a plurality of fastening elements passing through said holes for securing said propulsor housing to counter-sunk said under surface of said rearwardly extending upper portion.
 21. The watercraft of claim 20 wherein said prime mover includes a mounting flange by which said prime mover is secured to said upper surface of said rearwardly extending upper portion of said detachable member, said mounting flange having a plurality of counter-sunk openings which receive the heads of said fastening elements when said prime mover is secured to said upper surface.
 22. The watercraft of claim 19 and further including an impeller drive shaft, one end of which is in driving relationship with said impeller and the opposite end of which extends through an aperture in said propulsor housing into said passageway of said upper portion of said detachable member; and wherein the Operative connection between said output shaft of said prime mover and said impeller includes clutch means positioned in said passageway of said upper portion of said detachable member for selectively connecting said output shaft of said prime mover to said opposite end of said impeller drive shaft.
 23. The watercraft of claim 22 and further including: bearing means positioned in the aperture of said propulsor housing for rotatably supporting said impeller drive shaft therein; annular retaining ring means secured to said propulsor housing for retaining said bearing means in said aperture; the inner annulus of said annular retaining ring means being raised with respect to the remainder of said annular retaining ring means; a disk member fixedly secured to said impeller drive shaft slightly above said inner annulus for slinging water away from said aperture.
 24. The watercraft of claim 14 wherein said detachable member includes an inturned flange on a forward surface thereof, said flange having a plurality of apparatus through which fastening means may pass to secure said detachable member to said body member.
 25. The watercraft of claim 18 wherein said detachable member is of integral construction.
 26. The watercraft of claim 25 wherein said detachable member is a casting.
 27. The watercraft of claim 13 wherein said discharge opening is of predetermined diameter with respect to the output power of said motive means to thereby establish a predetermined discharge velocity with respect to the maximum forward speed of said watercraft.
 28. The watercraft of claim 27 wherein said predetermined discharge velocity is approximately twice the desired maximum forward speed of said watercraft.
 29. The watercraft of claim 27 wherein the diameter of said discharge opening lies in the range of 0.15-0.35 inches per horsepower of output of said motive means for motive means producing above 30 horsepower.
 30. The watercraft of claim 29 wherein the diameter of said discharge opening lies in the range of 0.35-0.5 inches per horsepower of output of said motive means for motive means producing below 30 horsepower.
 31. The watercraft of claim 13 wherein said detachable member includes an access channelway one end of which is in communication with said flow channel, and further including a cover member removably secured to said detachable member in closing relationship with respect to the opposite end of the said access channelway.
 32. Propulsor means for use on a buoyant body member; said propulsor means comprising: a detachable member removably secured to the rear of said body member, said detachable member having a flow channel therein, one end of said flow channel defining said inlet opening of said propulsor means; a propulsor housing secured to said detachable member, said propulsor housing having an intake opening in fluid communication with the opposite end of said flow channel, and an outlet opening which defines said discharge opening of said propulsor means; an impeller disposed in said propulsor housing intermediate said intake opening and said discharge opening; and motive means operatively connected to said impeller for rotating said impeller wherein said detachable member further includes a hollow section; and further including buoyant material disposed in said hollow section wherein said detachable member includes a rearwardly extending upper portion having an upper and lower surface, said propulsor housing being secured to said under surface and said motive means secured to said upper surface.
 33. Propulsor means for use on a buoyant body member; said propulsor means comprising; a detachable member removably secured to the rear of said body member, said detachable member having a flow channel therein, one end of said flow channel defining said inlet opening of said propulsor means; a propulsor housing secured to said detachable member, said propulsor housing having an intAke opening in fluid communication with the opposite end of said flow channel, and an outlet opening which defines said discharge opening of said propulsor means; an impeller disposed in said propulsor housing intermediate said intake opening and said discharge opening; and motive means operatively connected to said impeller for rotating said impeller; wherein said detachable member includes a rearwardly extending upper portion having an upper and lower surface, said propulsor housing being secured to said under surface and said motive means secured to said upper surface.
 34. The propulsor means of claim 33 wherein said upper portion includes a passageway therethrough; and said motive means includes a prime mover having an output shaft which is operatively connected through said elongated passageway to said impeller.
 35. The propulsor means of claim 34 wherein said upper portion of said detachable member includes a plurality of through holes disposed circumferentially about said passageway and further including a plurality of fastening elements passing through said holes for securing said propulsor housing to the said under surface of said rearwardly extending upper portion.
 36. The propulsor means of claim 35 wherein said prime mover includes a mounting flange by which said prime mover is secured to said upper surface of said rearwardly extending upper portion of said detachable member, said mounting flange having a plurality of counter-sunk openings which receive the heads of said fastening elements when said prime mover is secured to said upper surface.
 37. The propulsor means of claim 34 and further including an impeller drive shaft, one end of which is in driving relationship with said impeller and the opposite end of which extends through an aperture in said propulsor housing into said passageway of said upper portion of said detachable member; and wherein the operative connection between said output shaft of said prime mover and said impeller includes clutch means positioned in said passageway of said upper portion of said detachable member for selectively connecting said output shaft of said prime mover to said opposite end of said impeller drive shaft.
 38. The propulsor means of claim 37 and further including: bearing means positioned in the aperture of said propulsor housing for rotatably supporting said impeller drive shaft therein; annular retaining ring means secured to said propulsor housing for retaining said bearing means in said aperture; the inner annulus of said annular retaining ring means being raised with respect to the remainder of said annular retaining ring means; a disk member fixedly secured to said impeller drive shaft slightly above said inner annulus for slinging water away from said aperture.
 39. Propulsor means for use on a buoyant body member; said propulsor means comprising: a detachable member removably secured to the rear of said body member, said detachable member having a flow channel therein, one end of said flow channel defining said inlet opening of said propulsor means; a propulsor housing secured to said detachable member, said propulsor housing having an intake opening in fluid communication with the opposite end of said flow channel, and an outlet opening which defines said discharge opening of said propulsor means; an impeller disposed in said propulsor housing intermediate said intake opening and said discharge opening; and motive means operatively connected to said impeller for rotating said impeller wherein said detachable member further includes a hollow section; and further including buoyant material disposed in said hollow section; wherein said detachable member includes an inturned flange on a forward surface thereof, said flange having a plurality of apertures through which fastening means may pass to secure said detachable member to said body member.
 40. The propulsor means of claim 33 wherein said detachable member is of integral construcTion.
 41. The propulsor means of claim 40 wherein said detachable member is a casting.
 42. Propulsor means for use on a buoyant body member; said propulsor means comprising: a detachable member removably secured to the rear of said body member, said detachable member having a flow channel therein, one end of said flow channel defining said inlet opening of said propulsor means; a propulsor housing secured to said detachable member, said propulsor housing having an intake opening in fluid communication with the opposite end of said flow channel, and an outlet opening which defines said discharge opening of said propulsor means; an impeller disposed in said propulsor housing intermediate said intake opening and said discharge opening; motive means operatively connected to said impeller for rotating said impeller; wherein said discharge opening is of predetermined diameter with respect to the output power of said motive means to thereby establish a predetermined discharge velocity with respect to the maximum forward speed of said water craft; wherein said predetermined discharge velocity is approximately twice the desired maximum forward speed of said water craft; and wherein said detachable member includes a rearwardly extending upper portion having an upper and lower surface, said propulsor housing being secured to said under surface and said motive means secured to said upper surface.
 43. The propulsor means of claim 42 wherein the diameter of said discharge opening lies in the range of 0.15-0.35 inches per horsepower of output of said motive means for motive means producing above 30 horsepower.
 44. The propulsor means of claim 43 wherein the diameter of said discharge opening lies in the range of 0.35-0.5 inches per horsepower of output of said motive means for motive means producing above 30 horsepower.
 45. Propulsor means for use on a buoyant body member; said propulsor means comprising: a detachable member removably secured to the rear of said body member, said detachable member having a flow channel therein, one end of said flow channel defining said inlet opening of said propulsor means; a propulsor housing secured to said detachable member, said propulsor housing having an intake opening in fluid communication with the opposite end of said flow channel, and an outlet opening which defines said discharge opening of said propulsor means; an impeller disposed in said propulsor housing intermediate said intake opening and said discharge opening; and motive means operatively connected to said impeller for rotating said impeller; wherein said detachable member includes an access channelway one end of which is in communication with said flow channel, and further including a cover member removably secured to said detachable member in closing relationship with respect to the opposite end of the said access channelway.
 46. An oil slick recovery system comprising: a watercraft of the catamaran type having first and second spaced apart hulls joined by a deck, said deck having an opening intermediate said hulls; oil recovery means operatively positioned with respect to said opening to recover oil from the water in which said watercraft is floating; first and second propulsor means secured to the rear ends of said first and second hulls respectively for accepting water at an inlet opening and discharging water at a higher pressure at a discharge opening thereof; and a maneuverability system responsive to said first and second propulsor means for maneuvering said watercraft wherein said oil recovery means includes a roller positionable through said opening into said water, said roller having an absorbent covering thereabout; driving means for rotating said roller in the water; and pressure roller means engageable with said roller for squeezing the oil from absorbent covering; wherein said maneuverability system includes: first thrust generating means in fluid communication with Said discharge opening of said second propulsor means for generating thrust in a first direction about said turning axis; second thrust generating means in fluid communication with said discharge opening of said first propulsor means for generating thrust in a first direction, about said turning axis; third thrust generating means in fluid communication with said discharge opening of said first propulsor means for generating thrust in said second direction about said turning axis; fourth thrust generating means in fluid communication with said discharge opening of said second propulsor means for generating thrust in said second direction about said turning axis; and maneuverability control means on said body member for selectively establishing and nonestablishing the fluid communication between said first and second propulsor means and said first, second, third, and fourth thrust generating means.
 47. The oil slick recovery system of claim 46 and further including first collection chamber means in fluid communication with the discharge opening of said first propulsor means for collecting water discharged by said first propulsor means; and second collection chamber means in fluid communication with the discharge opening of said second propulsor means for collecting water discharged by said second propulsor means.
 48. The oil slick recovery system of claim 47 wherein said first collection chamber means includes an exit opening for permitting water to exit therefrom, and said second collection chamber means includes an exit opening for permitting water to exit therefrom; and further including first gate means secured to said first collection chamber means and movable between a first position in which the exit opening thereof is open, and a second position in which the exit opening of said first collection chamber is closed; and second gate means secured to said second collection chamber means and movable between a first position in which the exit opening of said second collection chamber means is closed.
 49. The oil slick recovery system of claim 48 and further including gate control means on said body member for selectively moving said first and second gate means between their respective first and second positions; movement of the respective first and second gate means towards their respective second positions causing their respective first and second collection chamber means to accumulate water at an increasingly higher pressure.
 50. The oil slick recovery system of claim 49 wherein the fluid communication between said discharge openings of said first and second propulsor means and the respective ones of said first, second, third and fourth thrust generating means is established by a plurality of fluid carrying conduits; a first conduit connected at one end there to said first collection chamber means and at its other end thereof to said first thrust generating means; a second conduit connected at one end thereof to said first collection chamber means and at its other end thereof to said second thrust generating means; a third conduit connected at one end thereof to said second collection chamber means and at its other end thereof to said third thrust generating means; and a fourth conduit connected at one end thereof to said second collection chamber means and at its other end to said fourth thrust generating means.
 51. The oil slick recovery system of claim 50 wherein said maneuverability control means includes: first, second, third and fourth pivoting vane means disposed in respective ones of said first, second, third and fourth conduits, each of said pivoting vane means being pivotally movable between a first position which blocks its respective conduit to prevent water flow therethrough, and a second position which opens its respective conduit to permit water flow therethrough; and manually operable maneuverability control stick means operatively connected to said plurality of pivoting vAne means for moving selected ones of said vanes between their first and second positions.
 52. The oil slick recovery system of claim 51 and further including fifth thrust generating means in fluid communication with said first collection chamber means for generating thrust on said body member in a rearward direction with respect to the forward direction of travel of said body member; and sixth thrust generating means in fluid communication with said second collection chamber means for generating thrust on said body member in a rearward direction with respect to the forward direction of travel of said body member; and reverse control means on said body member for selectively establishing and nonestablishing the fluid communication between said first and second collection chamber means and their associated fifth and sixth thrust generating means.
 53. The oil slick recovery system of claim 52 and further including a control panel; and wherein said manually operable maneuverability control stick means comprises: first, second, third and fourth control sticks operatively connected to said first, second, third and fourth pivoting vane means respectively; said first, second, third and fourth control sticks being movable on said control panel between first positions which correspond to their respective pivoting vane means being in their first, blocking position, and second positions which correspond to their respective pivoting vane means being in their second, open position; said first and fourth control sticks being grouped together and located on the starboard side of said control panel and movable between their first and second positions in a starboard direction; whereby simultaneous movement of said first and fourth control sticks in the starboard direction toward their second positions will cause said first and fourth thrust generating means to operate and move said body member in said starboard direction with respect to the longitudinal axis of said body member; said third and second control sticks being grouped together and located on the port side of said control panel and movable between their first and second positions in a port direction; whereby simultaneous movement of said third and second control sticks in the port direction toward their second positions will cause said third and second thrust generating means to operate and move said body member in said port direction with respect to said longitudinal axis of said body member.
 54. The oil slick recovery system of claim 49 wherein said first and second propulsor means are secured to the rear of said body member on opposite sides of said longitudinal axis thereof; said first and second collection chamber means are secured to said first and second propulsor means respectively on the rear side thereof; and said exit openings of said first and second collection chamber means face the stern of said body member; whereby the movement of said first and second gate means in selectively covering said exit openings of said first and second collection chamber means may be utilized to control the amount of forward thrust generated on said body member by said exit openings.
 55. The oil slick recovery system of claim 47 wherein each of said first and second propulsor means comprises: a detachable member removably secured to the rear of said body member, said detachable member having a flow channel therein, one end of said flow channel defining said inlet opening of said propulsor means; a propulsor housing secured to said detachable member, said propulsor housing having an intake opening in fluid communication with the opposite end of said flow channel, and an outlet opening which defines said discharge opening of said propulsor means; an impeller disposed in said propulsor housing intermediate said intake opening and said discharge opening; and motive means operatively connected to said impeller for rotating said impeller.
 56. The oil sLick recovery system of claim 55 wherein said detachable member further includes a hollow section; and further including buoyant material disposed in said hollow section.
 57. The oil slick recovery system of claim 56 and further including screening means secured to said detachable member and covering said inlet opening for preventing debris from entering said flow channel.
 58. The oil slick recovery system of claim 55 wherein said detachable member includes a rearwardly extending upper portion having an upper and lower surface, said propulsor housing being secured to said under surface and said motive means secured to said upper surface.
 59. The oil slick recovery system of claim 58 wherein said upper portion includes a passageway therethrough; and said motive means includes a prime mover having an output shaft which is operatively connected through said elongated passageway to said impeller.
 60. The oil slick recovery system of claim 59 wherein said upper portion of said detachable member includes a plurality of through holes disposed circumferentially about said passageway and further including a plurality of fastening elements passing through said holes for securing said propulsor housing to the said under surface of said rearwardly extending upper portion.
 61. The oil slick recovery system of claim 60 wherein said prime mover includes a mounting flange by which said prime mover is secured to said upper surface of said rearwardly extending upper portion of said detachable member, said mounting flange having a plurality of counter-sunk openings which receive the heads of said fastening elements when said prime mover is secured to said upper surface.
 62. The oil slick recovery system of claim 61 and further including an impeller drive shaft, one end of which is in driving relationship with said impeller and the opposite end of which extends through an aperture in said propulsor housing into said passageway of said upper portion of said detachable member; and wherein the operative connection between said output shaft of said prime mover and said impeller includes clutch means positioned in said passageway of said upper portion of said detachable member for selectively connecting said output shaft of said prime mover to said opposite end of said impeller drive shaft.
 63. The oil slick recovery system of claim 62 and further including: bearing means positioned in the aperture of said propulsor housing for rotatably supporting said impeller drive shaft therein; annular retaining ring means secured to said propulsor housing for retaining said bearing means in said aperture; the inner annulus of said annular retaining ring means being raised with respect to the remainder of said annular retaining ring means; a disk member fixedly secured to said impeller drive shaft slightly above said inner annulus for slinging water away from said aperture.
 64. An oil slick recovery system comprising: a watercraft of the catamaran type having first and second spaced apart hulls joined by a deck, said deck having an opening intermediate said hulls; oil recovery means operatively positioned with respect to said opening to recover oil from the water in which said water craft is floating; first and second propulsor means secured to the rear ends of said first and second hulls respectively for accepting water at an inlet opening and discharging water at a higher pressure at a discharge opening thereof; and a maneuverability system responsive to said first and second propulsor means for maneuvering said watercraft wherein each of said first and second propulsor means each comprise: a detachable member removably secured to the rear of said body member, said detachable member having a flow channel therein, one end of said flow channel defining said inlet opening of said propulsor means; a propulsor housing secured to said detachable member, said propulsor housing having an intake opening in fluid communication with the opposIte end of said flow channel, and an outlet opening which defines said discharge opening of said propulsor means; an impeller disposed in said propulsor housing intermediate said intake opening and said discharge opening; and motive means operatively connected to said impeller for rotating said impeller; wherein said detachable member includes a rearwardly extending upper portion having an upper and lower surface, said propulsor housing being secured to said under surface and said motive means secured to said upper surface. 